Get the indices of the n largest elements in a matrix

Question

Suppose I have the following matrix:

01 02 03 06
03 05 07 02
13 10 11 12
32 01 08 03

And I want the indices of the top 5 elements (in this

Answer 1

If you have a rather big array and only want a few elements out of it. This would be my solution.

Arraycopy = Array;
for j = 1:n
   [a, Index(j)] = max(Arraycopy);
   Arraycopy(Index(j)) = -inf;
end
maximumValues = Array(Index);

I think it should be faster and less RAM demanding than the sort solution.